Or, as a realistic ideal, as little as you possibly can.
On the other other hand I ferociously criticise bad ideas.
People are not their ideas. Bad ideas are like mimetic parasites, replicating through and infecting a host.
Some bad ideas are harmless opinions. Other bad ideas are a grave harm to their host, and society around them.
While people jave every "right" to hold them, sometimes attacking bad ideas seems like an attack on a person (ad hominem), which should be consciously avoided. A person, qua soul, is seldom even responsible for what they host and parrot [1]. But they are responsible for spreading those ideas, which is why teachers, parents and trash social media have much to answer for. And, I believe, it is a duty and responsibility to help people be free of bad ideas, or if possible to steer them away from them. By the same token I believe people who spread bad ideas for profit and personal gain are the most damaged, and damaging of all.
It is a shame in our presently over-defensive culture where people identify with their ideas that the reaction of some people is to perceive an attack on them-self, as a person. Good criticusm of bad ideas should always be welcome.
[1] https://genius.com/Smog-vessel-in-vain-lyrics https://www.youtube.com/watch?v=DoiNXDpDkok